Multicylinder hot gas reciprocating piston engine of the doubleacting type



Sept. 23, 1952 F. VAN WEENEN 2,611,235

MULTICYLINDER HOT GAS RECIPROCATING PISTON ENGINE OF THE DOUBLE-ACTING TYPE Filed 001'. '7, 1949 INVENTOR. LAMBERTUS VAN WEENEN FRANCSCUS AGENT Patented Sept. 23, 1952 v 2,611,235 MULTICYLINDER HOT GAS RECIPROCAT- IN G PISTON ACTING TYPE Franciscus Lambertus va Netherlands, assignor Bank and Trust Company, Hartford, Conn., as

trustee ENGINE OF THE DOUBLE- n Weenen, Eindhoven, to Hartford National Application October 7, 1949, Serial No. 120,047 In the Netherlands October 12, 1948 3 Claims.

This invention relates to double acting hot-gas reciprocating engines comp-rising at least four cylinders arranged in a row, in which it is not necessary for the centre lines of the cylinders to lie in a plane. The term hot-gas reciprocating engines is to be understood to include refrigerating machines operating according to the reversed hot-gas engine principle.

According to the invention, -a double actin hot-gas reciprocating engine comprising at least four cylinders arranged in a row is characterized in that the two working spaces of the first cylinder and the two working spaces of the last cylinder of the row are each in free communication with a working space associated with the same cycle in a cylinder arranged between the first and the last cylinder of the row.

As a rule, multi-cylinder hot-gas reciprocating engines in which the cylinders are arranged in a row are constructed as follows. The space above the piston of the first cylinder is in free communictaion with the space below the piston of the second cylinder, the space above the piston of the second cylinder with the space below the piston of the third cylinder and the space above the piston of the last cylinder with the space below the piston of the first cylinder. This arrangement has the advantage that most of the junction channels between the spaces are very short so that the clearance volumes of the cycles taking place in these working spaces are small. A disadvantage is, however, that the junction channel between the last and the first cylinder is very long. Due to this the clearance volume of the cycle taking place in the first cylinder and the last cylinder is very large. In addition, the heat losses are considerable due to the great length of the channel. The efiiciency of this cycle may, therefore, be greatly decreased due to the considerable clearance volume and the considerable heat losses.

In the arrangement according to the invention, this disadvantage is mitigated in that a junction channel is not provided between the first and the last cylinder. In this manner it is achieved that the lengths of the channels are more uniform, since there is no very long junction channel. In this event, some channels may be longer than in the aforesaid known construction, but the total efficiency of the engine according to the invention is greater owing to the uniformity of the different cycles. In addition, the engine operates more quietly.

According to one feature of the invention one working space of each of the first and the last cylinders of the row may be in free communication with a working space in the adjacent cylinder, and the other working space of each of the first and the last cylinders may be in free communication with a working space in the cylinder next to the adjacent cylinder.

Thus, it is ensured that all the junction channels between the spaces are comparatively short. In addition, a substantially symmetrical positioning of the channels is possible with diiferent numbers of cylinders. A particular advantage consists in that the engine may, for instance, comprise two groups of equal channels, which permits junction channels to be interchanged.

Both the lengths and the diameters Of the junction channels between all the cylinders may be of the same order of magnitude, withthe result that all the cycles occurring in the cylinders are identical. Moreover, correct positioning of the channels permits junction channels to be interchanged, the heater, regenerator and cooler of each cycle being identical.

In order that the invention may be more clearly understood and readily carried into efiect, it will now be described more fully with reference to the accompanying diagrammatic drawing,'given by way of example, in which:

Fig. 1 represents one embodiment of a sixcylinder hot-gas reciprocating engine according to the invention, and

Fig. 2 represents one embodiment of a fourcylinder hot-gas reciprocating engine according to the invention, comprising four junction channels of equal length.

The six-cylinder hot-gas reciprocating engine shown in Fig. 1 comprises six cylinders I, 2, 3, 4, 5, 6 in which pistons I 2 3 4 5 and 6, respectively, are movable. By means of a. piston rod and a connecting rod each piston is connected to a crank shaft l which is supported in a suitable manner in bearings. The space above piston I is in free communication through a junction channel 8 with the space below piston 2 the space above piston 2 through a junction channel 9 with the space below piston 3 the space above piston 3 through a junction channel It] with the space below piston 4 the space above piston 5 through a junction channel I I, to the space below piston 5 the space above piston 5 through a junction channel 12 with the space below piston 6 and the space above piston 6 through a junction channel l3 with the space below piston E so that each space is in free communication with another space. The junction channels 8, 9, In, H, l2 and 13 contain a heater, a regenerator and a cooler (not shown). Similarly to the engines hitherto known, all spaces above the pistons in the different cylinders are similar i. e. all working spaces are hot or cold spaces, and all working spaces below the pistons are also similar. In the present case, the working spaces above the pistons may be hot spaces, and the spaces below the pistons may be cold spaces. In hot-gas reciprocating engines, expansion occurs substantially in the hot space, whereas compression occurs substantially inthe cold space. The junction channels 8, m, l2 are of substantially the same length, and the other group of junction channels viz. 9, ll, [3 are also of substantially the same length. Since the lengths of the channels associated with the different groups are very much the same, the chiciency of the cycles will likewise be substantially equal.

The four-cylinder hot-gas reciprocating engine shown in Fig. 2 comprises four cylinders arranged in a row viz. cylinders 2 I, 22, 23, 24 in which the pistons 2 I 22, 23 and 24 respectively are movable. In this case also it is assumed that the spaces above the pistons 21, 22 23 24 are the hot spaces and the spaces below these pistons arethe cold spaces. The hot space of cylinder 2| is in free communication through a junction channel 25 with the cold space of cylinder 22, the hot space of cylinder 22 through channel 23 with the cold space of cylinder 23, the hot space above piston 23 through channel 21 with the working space below piston 24 and the hot space of cylinder 24 through junction channel 28 with the cold space of cylinder 2 I. The junction channels 25, 26, 27, 28 may each house a heater, a regenerator and a cooler (not shown). The lengths of all the junction channels are of substantially the same length, so that the cycles may be completely uniform. It will be appreciated that an arrangement similar to that shown in Figure 2 wherein one cycle takes place in the first cylinder and in the adjacent cylinder, and another cycle takes place in the first cylinder and the next but one adjacent cylinder, as is also the case with the last cylinder, mayreadily be used in hot-gas reciprocating engine having more than four cylinders. The pistons ZI 22 23 24-- are linked to a crankshaft 2% in the usual manner. diameters of the junction channels are of the same order of magnitude, the heater, regenerator and cooler of one junction channel may be exactly similar to the heater, regenerator and cooler of any other channel.

What I claim is:

1. A hot gas engine comprising a plurality of Where both the lengths and the cylinder means arranged in a row and including two end cylinder means and at least two intermediate cylinder means, a plurality of reciprocating members arranged one in each cylinder means and forming therewith a hot working space and a cold working space adapted to receive a working gas, means interconnecting said reciprocating means to cause each working space of each end cylinder means to operate in the same cycle with a Working space of one of said intermediate cylinder means, and a plurality of connections for the passage of the working gas each connection connecting the hot space of one cylinder means to the cold space of another cylinder means, the connection connected to the hot space of each end cylinder means being connected to the cold space located in an intermediate cylinder means and operating in the same cycle and each connection connected to the cold space of each end cylinder means being connected to the hot space located in an intermediate cylinder means and operating in the same cycle.

2. A hot-gas engine comprising a plurality of cylinder means arranged in a row and including two end cylinder means and at least two intermediate cylinder means, a plurality of reciprocating members arranged one in each cylinder means and forming therewith a hot working space and a cold working space adapted to receive a working gas, means interconnecting said reciprocating means to cause one working space of each end cylinder means to operate in the same cycle as a working space of the adjacent intermediate cylinder means and the second working space of each end cylinder means to operate in the same cycle as the working space of a cylinder means next to the adjacent cylinder means, and a plurality of connections for the passage of the working gas each connection connecting the hot space of one cylinder means to the cold space of another cylinder means, each of the connections connected to one working space of each end cylinder means being connected to the working space located in the adjacent cylinder and operating in the same cycle, each of the second working spaces of each end cylinder means being connected to the working space located in the cylinder means next to the adjacent cylinder means and operating in the same cycle.

3. A hot gas engine as defined in claim 1 in which the connections between the hot spaces and the cold spaces have substantially the same lengths and cross-sectional areas.

FRANCISCUS LAMBERTUS VAN WEENEN.

No references-cited. 

